1) Field of the Invention
The present invention relates to a door device and particularly relates to a door device that has two doors to close a single opening in a vehicle body.
2) Description of the Related Art
Some of the vehicles are provided with a door device that has a hinged front door and a slidable rear door and there is no center pillar between the two doors. In other words, these door devices have a so-called center-pillarless-structure. The center pillar becomes an obstruction when entering the vehicle; however, it gives sturdiness to the vehicle and protects the people inside the vehicle in case of a side collision. Since these vehicles do not have the center pillar they need some protective measures in case of a side collision.
As a safety measure against side collisions, such door devices have an interlock mechanism. This interlock mechanism locks the doors to each other when both the doors in closed states. This interlock mechanism includes a striker in one of doors, and a latch unit, which engages with the striker, in the other door. The latch unit includes a close actuator, which interlocks the doors when they are in the closed states. The latch unit further includes a release actuator, which releases the lock of the doors when the doors are opened. Such a door device has been disclosed in Japanese Published Unexamined Patent Application No. 2004-27726.
However, according to the conventional door device, the doors are locked when they are in the closed states; in other words, it need to be first detected whether the doors are in the closed states before actuating the close actuator. Erroneous operation prevention control, premised on the erroneous detection of the closed states despite the doors being in opened states, is thus required. Also, when the rear door is made to open and close automatically, the actuation of the respective actuators of the interlock mechanism must be controlled in accordance with the automatic opening and closing of the rear door. Complex operations, which are in accordance with the opening and closing of the doors, are thus required with the conventional door device.
Moreover, since the interlock mechanism is actuated by means of actuators, when a malfunction of the electrical system, such as an actuator malfunction or malfunction of a detection unit for detecting the closed state of the respective doors, occurs, the action of the interlock mechanism becomes disabled or the doors become unable to be opened in a normal door opening operation. In addition, since the two actuators of the close actuator and the release actuator are used, the cost is high.